Locomotive steam throttle-valve.



O. MEHLHOFE.

LOGOMOTIVE STEAM THROTTLE VALVE.

APPLIOATION FILED JUNE 28, 1912.

1,070,1 57, Patented Aug. 12, 1913.

CHRIS-T -M.EIILHOFE, 0F .MORSE, SASKATCHEWAN, CANADA.

"'IiOC'OM OTIVE STEAM THROTTLE-VALVE.

Specification of Letters Extent.

Patented A11 12,1913.

To-aZZ whom it 'm'ay'comern Be "it known t-hat I, Orrmsr MnHLHor-n, a

subject of the "King of 'Great Britain, resid- *ing at hIorse,'in-"tl1e Province of Saskatchewan and Dominion'o'fCanada, have invented new and "useful Improvementsin Locomotive Steam Throttle-valves of which the following 'is :a specification.

This invention relates to certain noveland useful improvements in throttle valves and has particular application to valveso'f this type for use in the stea-mdomes of locomotive boilers for establishing a-nd'cutting offcommunication between said domeand the engine cylinders.

In carrying out the present invention, itis my purpose to provide a steam engine-throttle valve which when closed will effectively cut off communication between the steam dome of the boiler and the cylinders of the engine, and, when open will be held against accidental closing, thereby insuring open communication between the steam dome and the cylinders of the engine.

Furthermore, I aim to provide a throttle valve which will be manually operable to open and closed positions and held in open position by the action of the steam, thereby eliminating rattling of the valve and, accidental movement thereof.

A still further object of my invention is the provision of a throttle valve which will embrace the desired features of simplicity, efliciency and durability and which will be freely movable to open and closed positions and held in such positions automatically and independently of the usual notched quadrant and locking dog usually employed with throttle levers.

l/Vith the above and other objects in view, the invention consists in the construction, combination and arrangement of parts hereinafter set forth in and falling within the scope of the claim.

In the accompanying drawing; Figure 1 is a fragmentary sectional View through the steam dome of a boiler showing my invention applied thereto, parts being shown in elevation, and Fig. 2 is a detail perspective view of the throttle valve.

' Referring now to the accompanying drawing in detail, A designates the steam dome of a locomotive boiler, from which leads the usual steam main B for conveying the steam to the engine cylinders. Formed integral with the steam main B or connected thereto :tube 1 and sliding within such tube.

in: any suitable manner and arranged within the steam-dome A, is a tapering tube 1 pro-- vided approximately centrally of its length with a steam inlet 2 and housing the throttle valve 3, the latter being preferably of the piston valve typeand is tapered-to conform to the=configuration of the interior of the The free end of the tube 1 is closed by means of a cap or plug 4- provided with a centrallyarranged aperture through which is passed the valve actuating rod 5 having one end secured to the-throttle valve while the opposite end is connected to the operating lever 6 movable about the usual notched quadrant 7 and equipped with a locking dog 8 under the influenceof a draw rod 9.

The throttle valve 3 as shown more particularly in Fig. 2, is composed of a plurality of relatively large flexible rings 10 disposed concentrically about a metallic sleeve 11 and held spaced apart by means of small washers 12 also disposed concentrically of the sleeve 11 and arranged between the proximate faces of the rings, the adjacent end of the valve actuating lever 5 being passed through the sleeve 11 and held therein by means of nuts 13, 13 threaded onto the valve lever at the opposite ends of the valve. This valve 3, as before stated, is of a tapering contour to conform to the shape of the tube 1 and is of a length equal to the distance between the steam inlet port 2 and the opposite ends of the tube, so that when the valve is moved to an open position, the forward end thereof will be disposed rearwardly of the steam inlet 2 with respect to the steam main B whereby the steam issuing from the dome into the steam main will act upon the adjacent face or end of the valve to maintain the same in open position, while, on the contrary, when the valve is closed, the rear end thereof will be disposed in advance of the steam inlet 2 with respect to the main B, whereby the steam within the steam dome will enter the tube between the plug or cap 4 and the confronting end or face of the valve with the effect to hold the same in closed position, the flexible rings 10 bending backwardly when the valve is in closed position. On the other hand, when the valve is moved to open position, the rings 10, being flexible, permit the escape of steam from behind the valve.

From the foregoing description taken in connection with the accompanying drawing,

the construction, mode of operation and manner of employing my invention will be readily apparent.

It will be seen that I have provided a simple, yet efficient and durable form of valve which may be readily and quickly actuated to open and closed positions and which will be maintained in open and closed positions by the action of the steam.

l/Vliile I have herein shown and described one preferred form of my invention by way of illustration, I wish it to be understood that I do not limit myself to the precise details of construction herein described and delineated, as modification and variation may be made without departing from the spirit of the invention or exceeding the scope of the claim.

I claim:

In a throttle valve, the combination with a steam dome, of a steam main adapted to have communication with said dome, a

tapering tube in communication with said main and disposed within the dome and provided with a steam inlet approximately centrally of its length, a piston valve slidably disposed within the tube and comprising a plurality of rings, and washers disposed between the proximate surfaces of the rings and holding the same spaced apart, said valve being of a configuration corresponding to that of the tube and of a length equal to the distance between the steam inlet and the opposite ends of the tube whereby the valve may be maintained in open and closed positions by the action of the steam, and means for moving said valve to open and closed positions.

In testimony whereof I affix my signature in presence of two witnesses.

CHRIST MEHLHOFF. Witnesses ERNEST Gnnennronn, ROY SHEPPARD.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

